package com.fessc.develop.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

import java.util.concurrent.ThreadPoolExecutor;

@Configuration
@EnableAsync
public class AsyncThreadConfig {

    private static int CORE_POOL_SIZE = 10;	//核心线程数
    private static int MAX_POOL_SIZE = 20;  //最大线程数
    private static int QUEUE_CAPACITY = 20;	//队列容量
    private static int KEEP_ALIVE_SEC = 300;  //线程活跃时间（秒）

    @Bean(name="AsyncThreadExecutor")
    public ThreadPoolTaskExecutor taskExecutor() {
        //newFixedThreadPool
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        // 设置核心线程数
        executor.setCorePoolSize(CORE_POOL_SIZE);
        // 设置最大线程数
        executor.setMaxPoolSize(MAX_POOL_SIZE);
        // 设置队列容量
        executor.setQueueCapacity(QUEUE_CAPACITY);
        // 设置线程活跃时间（秒）
        executor.setKeepAliveSeconds(KEEP_ALIVE_SEC);
        // 设置默认线程名称
        executor.setThreadNamePrefix("asyncExecutor-");
        // 设置拒绝策略
        // rejection-policy：当pool已经达到max size的时候，如何处理新任务
        // CALLER_RUNS：不在新线程中执行任务，而是由调用者所在的线程来执行
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        // 等待所有任务结束后再关闭线程池
        executor.setWaitForTasksToCompleteOnShutdown(true);
        executor.initialize();
        return executor;
    }
}
